Nowadays, an imaging device such as a digital still camera, a digital video camera or the like, which includes an image sensor such as a CCD or a CMOS, has seen an explosive prevalence. In general, the imaging device which detects a focusing state based on an image signal of an object and performs auto-focusing control by moving, based on a result of the detection, a focusing lens unit included in an imaging optical system in an optical axis direction has been prevailing.
Accompanied with an increase in functionality of an imaging device, sophistication in a function of auto-focusing control has been demanded. For example, an auto-focusing device which is adapted to the imaging device and performs focusing adjustment is disclosed in patent document 1. The auto-focusing device segments an image signal of an object into a plurality of focus areas, counts the number of skin color pixels included in each of the focus areas, and specifies one focus area used for the focusing adjustment.
In the conventional auto-focusing device disclosed in the patent document 1, a person is assumed as a main object. In other words, the auto-focusing device performs focusing control based on the skin color pixels so that the focus area follows a person, thereby invariably allowing accurate focusing on a person.
[Patent document] Japanese Laid-Open Patent Publication No. 2004-37733